Clamping and articulation element

Abstract

A one-piece clamping element has two opposing clamping jaws forming a laterally open cavity to receive a rod-shaped element. A hinge is located between the jaws, arranged opposite the cavity, and connecting the clamping jaws with one another and thus allowing them to be movable with respect to one another. Each clamping jaw has one bore, aligned flush with one another. One clamping jaw has a receptacle for an anti-rotation device. The receptacle makes it preferable—with the exception of an immediate tightening of the screw in this or another place of an external fixator clamping element used for the same patient—to use the clamping element only once and discarding it after use. Two identical clamping elements, with the possible exception of the size of the rod receptacle, can be placed on top of one another to form an articulation element.

1. A one-piece clamping element comprising two opposing first and second clamping jaws forming a laterally open cavity to receive a rod-shaped element and at least one internal hinge arranged opposite the cavity connecting the two opposing clamping jaws to one another and thereby making them movable towards and away from one another, with each clamping jaw having a bore aligned with one another, wherein the hinge is resilient and that the bores are arranged between the cavity and hinge wherein the hinge includes two resilient lateral bars, which each merge into the first and second clamping jaws wherein the lateral bars include a resilient and primarily C-shaped portion on the side of the clamping element opposite the cavity, each of which merges into the first and second clamping jaws wherein each bar has engagable part-cylindrically-shaped protrusion and complementary groove acting as stops, which allow a pre-determined distortion about an axis of the resilient lateral bars before the stops come into engagement. 
   
   
     2. The clamping element as set forth in  claim 1 , wherein a first clamping jaw has an anti-rotation device on its exterior or a receptacle for receiving an anti-rotation device. 
   
   
     3. The clamping element as set forth in  claim 1 , wherein the hinge includes a resilient hinge wall, which merges into two parallel ribs formed on said first and second clamping jaws, which ribs run past the bore and which end in an area of a free end of at least one of the clamping jaws or which merge into the body of the one clamping jaw. 
   
   
     4. The clamping element as set forth in  claim 1 , wherein the lateral bars include a semi-circular centerpiece, followed at one end by a first bar portion having an end integral with a first side of the first clamping jaw and followed at a second end by a second bar portion integral with a first side of the second clamping jaw, the second bar portion longer than the first bar portion. 
   
   
     5. The clamping element as set forth in  claim 4 , wherein the longer bar is in the area of a wall adjacent to the cavity and is connected with the second clamping jaw in the form of a rib. 
   
   
     6. The clamping element as set forth in  claim 1  wherein the lateral bars are separated laterally from the clamping jaws by a slit. 
   
   
     7. The clamping element as set forth in  claim 1  wherein the lateral bars include a resilient and primarily C-shaped portion on the side of the clamping element opposite the cavity, each of which merges into the first and second clamping jaws wherein each bar has an engagable part-cylindrically-shaped protrusion complementary and groove acting as stops, which allow a pre-determined distortion about an axis of the resilient lateral bars before the stops come into engagement. 
   
   
     8. The clamping element as set forth in  claim 1  wherein the bore in the first clamping jaw is cylindrical and has a longitudinal alignment rib. 
   
   
     9. The clamping element as set forth in  claim 8  wherein the bore in the second clamping jaw conically narrows in the direction of the first clamping jaw and has an enlarged diameter step to receive the head of a screw or a nut. 
   
   
     10. The clamping element as set forth in  claim 9  wherein the bore has a lateral recess for receiving an anti-rotation device of the nut. 
   
   
     11. An articulation element having first and second clamping elements as set forth in  claim 1 , which clamping elements are arranged on top of one another with their first clamping jaws adjacent one another, and having an at least two-piece locking shaft with a first part of the locking shaft insertable through a bore of the second clamping jaw the first clamping element, and with a second part of the locking device insertable through a bore of the first clamping jaw of the second clamping element, and with one or the other or both parts being able to be brought in contact with one another through the bores in the first clamping jaws, and where the first and second clamping jaws of the first and second clamping elements can be blocked with the locking device. 
   
   
     12. The articulation element as set forth in  claim 11 , wherein an anti-rotation device is arranged between the first clamping jaws that are arranged on top of one another, the anti-rotation device having a central bore. 
   
   
     13. The articulation element as set forth in  claim 12 , wherein the anti-rotation device is a plate whose material is harder than the material of the clamping elements and which has ridges formed on both sides of the plate. 
   
   
     14. The articulation element as set forth in  claim 12 , wherein the anti-rotation device is a cylinder whose material in a floor and a lid area is preferably harder than the material of the clamping elements, and which consists of a flexible, compressible material in the solid material part, in particular synthetic foam. 
   
   
     15. The articulation element as set forth in  claim 11 , wherein the locking device includes a cylindrical screw and a conical nut, and that the conical nut preferably has a stop shoulder for a self-locking screw which can be inserted in an internal thread in the cylindrical screw. 
   
   
     16. The articulation element as set forth in  claim 11 , wherein a hollow spring enveloping the locking device is used as an anti-rotation device or as an additional anti-rotation device. 
   
   
     17. A one-piece clamp for clamping rods of an external fracture fixation system comprising:
 molded polymeric first and second jaw elements having an axial bore therethrough, said jaw elements connected on a first side of said axial bore by an integrally molded hinge element, each jaw element having a laterally open groove spaced from said axial bore on a second side thereof for receiving said rods, wherein the hinge includes two spaced resilient lateral bars, which each merge into the first and second jaw elements wherein the lateral bars each include a resilient and primarily C-shaped bar on the side of the clamp opposite the cavity, each of which merges into the first and second jaw elements wherein the lateral bars each have at least two complementary engagable part-cylindrically-shaped elements, one of which is a groove, acting as stops, which allow a pre-determined distortion about an axis of the resilient lateral bars before the stops come into engagement. 
 
   
   
     18. The clamp as set forth in  claim 17 , wherein the hinge includes a resilient hinge wall, which merges into two parallel ribs formed on said first and second jaw elements, which ribs run past the bore and which end in an area of a free end of at least one of the jaw elements or which merge into the body of the one jaw element. 
   
   
     19. The clamp as set forth in  claim 18 , wherein the lateral bars include a semi-circular centerpiece, followed at one end by a first bar portion having an end integral with a first side of the first jaw element and followed at a second end by a second bar portion integral with a first side of the second clamping jaw, the second bar portion longer than the first bar portion. 
   
   
     20. The clamp as set forth in  claim 19 , wherein the longer second bar portion is in the area of a wall adjacent to a cavity for receiving a rod and is connected with the second jaw element in the form of a rib.